Background--The average child spends as much time viewing movies and television as he spends in school. Tobacco use is ubiquitous in movies, yet its impact on adolescent smoking has not been studied before. We hypothesize that exposure to tobacco use in movies is a causal element in the initiation of adolescent smoking. Preliminary Work-- Our 4-year study resulted in a content analysis measuring the amount and context of tobacco use in over 600 popular contemporary movies. We found tobacco depictions in 95% of the movies and brand appearances in 28%. We linked these data with responses from a cross-sectional study of over 5000 5% 8_ grade students. In a multivariate analysis, adolescent exposure to tobacco use in movies was associated with adolescent smoking and, among never smokers, it was associated with attitudes that predict future smoking. Specific Aims--The goal of this application is to better understand the relationship between viewing tobacco use in movies and adolescent smoking. To accomplish this, we plan to continue the content analysis of popular contemporary films through the year 2005 and conduct a two-year longitudinal telephone survey of a nationally representative sample of 3000 adolescents. This survey will enable us to describe adolescents' exposure to tobacco use in contemporary films over time and to determine if this exposure predicts smoking uptake. Methods--Adolescents will be surveyed semiannually about their smoking status, exposure to a sample of recently released popular movies, and a number of other factors related to adolescent smoking. Each survey will contain a unique subset of movies, randomly selected from top box-office hits and video rentals released within six months prior to the survey. The primary outcome will be the transition from never smoker to experimenter. Secondary analyses will be conducted to examine whether exposure to movie tobacco use influences a t titudes among never smokers and influences experimenters to become established smokers. We will also evaluate differences in movie exposure among whites, African Americans, and Latinos. Significance-- This is the first prospective study to evaluate the public health implications of depicting tobacco use in movies. Because our study involves a nationally representative sample of U.S. adolescents, data from this survey will enable us to determine the number of cases of youth smoking in the United States that are attributable to exposure to tobacco use in popular, contemporary movies.